House Rules - Fixing Ship Fuel Operational Times

[phavoc]

In mongoose, computers are included in bridge tonnage and electronics tonnage is separate; but the difference is the same.

Yes. As it has been in some other variations of Traveller. As I stated in my original point, in the original version of Traveller computer systems took up tonnage. So we agree on this point.

That is one valid interpretation.

I'm not interpreting them at all. I'm stating them as written.

Perhaps in some peoples TU the power plant is either on or off and can't "throttle back"?

I find it strange when there are many ways of interpreting something, there are some people that chose to stick with the one that counters their logic instead of coming up with an interpretation that fits their needs. So be it. It's your interpretation.

The question of fuel usage has been around for quite some time. The main rules have been slightly tinkered with since CT was published, but none of the canon sets really addressed this point. Many people have posted their own house rule alterations (or interpretations). You can find them here, and in other Traveller places.

You assume that by my stating what the book (i.e. the canon ruleset) that somehow that's how I handle things. You assumed wrong.

To me, the more important question is game playability. There could be a game where every weapon, piece of electronics, recharging the vacc suit batteries, the coffee maker, lighting at full vs half, and so on has a power consumption rating and the players need to calculate exactly how much is consumed every week, every day, every hour, every moment of "operation"? Some people do love that nitty gritty stuff. "Captain, someone left the sensors powered up while we were in Jump. Were going to be cutting it close on fuel."

When the rules say "Fuel 44 tons One Jump–2 and two weeks of operation" I don't take this to mean the ship can only do Jump 2 and Jump 1 is impossible.

Nor do I take a generic "week of operation" to mean any and all ship activity. I don't have the capability to memorize all the rules. Please point me to any rules that are more specific on this.

The rules do actually cover how jump works. If you'll re-read the section on how jumps work you'll see that a ship with a Jump 4 drive can do 4 Jump 1s, two Jump 2s, a Jump 3 and a Jump 1, or a single Jump 4. However, the rules do also state that your power plant fuel consumption rates don't change, so if you did not have enough fuel set aside to power your ship (or have an alternative power plant available) you'll run out of fuel for your power plant and will potentially re-enter space with zero fuel after your last successful jump. That's assuming, of course, that you had sufficient fuel to create the jump bubble in the first place.

To your comment about tracking power down to the coffee maker, I've really yet to run into a person who cares about every watt of power generated. Some would like to be able to know that, for example, your Type A fusion plant produces 5 points of power. Your M-Drive takes 2 points, your two beam lasers in your triple turret take 2 points, life support and ship systems take 1 point (which covers the coffee maker) which leaves 0 points available. If you wanted to add a third laser, or say replace your lasers with a single particle accelerator, then you'd also need to either upgrade your power plant or use your M-Drive at 50% power if you were firing all of your weapons.

All ship designs involve trade-offs. Having more information on the underlying systems allows those that are interested to make different decisions.

Probably half or more of the posts and responses here on the board are in regards to the rules and tweaks/changes/house rules. Isn't that kind of the point of discussions? To share views and thoughts and for each person to take away from it what they will?

[/quote="Reynard"]"Who was in the store room and left the lights on! We're not made of money!! I don't care if you're cold, leave the life support off and dress warmer!"[/quote]

It was Bob! Cap'n says he's gonna lose a ship-share because he left the airlock open too last week.

 

[Reynard]

"so if you did not have enough fuel set aside to power your ship (or have an alternative power plant available) you'll run out of fuel for your power plant and will potentially re-enter space with zero fuel after your last successful jump. "

That's classic Darwinism and a reason for smart player to find those drifting ships with the dead crews. That's why the game makes it clear you NORMALLY make one Jump then spend a week (or more if you get more fuel to tool around the planets) doing Traveller things before heading for you next system. At most, you may exit Jump in a system near a gas giant to refuel then Jump out as soon as you're full.

"Guys! You know our ship is Jump 3. We can save money if we hop from one Jump 1 system to the next without stopping to refuel! We'll be rich!..."

"ANOTHER dead ship?! Don't they demand pilot tests before selling these machines?"

 

[Condottiere]

Less abstract would be calculating the exact energy footprint of every component on the ship, and then seeing if it's viable to activate them as and when required. However, Mongoose hasn't quite taken that route.

Solar panels reduce fuel consumption by seventy five percent at minimal manoeuvring, which presumably means gravitic drives, not reaction ones (actually, the entire issue is unclear, since reaction drives seem to need minimal power from the generators).

 

[phavoc]

"so if you did not have enough fuel set aside to power your ship (or have an alternative power plant available) you'll run out of fuel for your power plant and will potentially re-enter space with zero fuel after your last successful jump. "

That's classic Darwinism and a reason for smart player to find those drifting ships with the dead crews. That's why the game makes it clear you NORMALLY make one Jump then spend a week (or more if you get more fuel to tool around the planets) doing Traveller things before heading for you next system. At most, you may exit Jump in a system near a gas giant to refuel then Jump out as soon as you're full.

That's true. Of course some players may tangle with the wrong ship and have to jump out or risk destruction. Not that a referee would ever do such a thing...

Under normal conditions it's not necessarily wrong or a bad idea for a ship to only have two weeks of power plant fuel. For jump-capable ships it's usually less than a day to reach the jump clearance zone, another week or so spent in jump space, and then a day to dock somewhere. So that leaves a ship with say five days reserve. Pretty reasonable under perfectly normal and ideal conditions. Which can make for a boring adventure for most.

As I mentioned up-thread, it's not very reasonable for military ships to be left with such a small reserve. Granted a defender can't totally defend all sources of fuel in a system, so you can always find someplace to get it. But if you jump in and find the defender too strong at the 1st gas giant, you may not have enough fuel to get to another one before you tanks run dry, let alone have to fight and maneuver before you get a chance to tank up. If you brought along some tankers that gives you more flexibility, but fleet trains aren't detailed much in the source materials, and jumping with a sizable tanker reserve gives you maneuver options, but you are stuck until you can refuel.

And "Assignment: Vigilate" has rules for partial power and fuel consumption IIRC. The complete set from FFE on DVD ist < 50€

I have that (in hardcopy and soft). I will have to take a look at that. Thanks for pointing it out.

 

[Reynard]

You mean SDBs are actually useful denying fuel to invading fleets?! Where's that other thread?

Any fleet or strike squadron should never be jumping blind into conflicts. Intel should establish what fuel sources are available and any possible opposition might be expected. Tankers would be with squads and fleets to refuel crucial ships at exit if there is expected opposition but again, any ship will have fuel for at least a week as fuel points are secured. No Group plans to fail. You go in with what gets the job done.

 

[phavoc]

You mean SDBs are actually useful denying fuel to invading fleets?! Where's that other thread?

The SDB writeups have always talked about the 'vulnerability' of a refueling ship, but I've yet to come across the paragraph that actually sets some limits to it. Min/max SDB's can be pretty deadly for their size, and a swarm of them can chew up lightly armored ships and disappear before help can arrive.

Any fleet or strike squadron should never be jumping blind into conflicts. Intel should establish what fuel sources are available and any possible opposition might be expected. Tankers would be with squads and fleets to refuel crucial ships at exit if there is expected opposition but again, any ship will have fuel for at least a week as fuel points are secured. No Group plans to fail. You go in with what gets the job done.

You always jump blind into a system. Any intel you might get will be two weeks old - one week to jump to the waiting fleet with the info, one week to jump back into the system. Thus your info is always at least two weeks old.

Rumsfeld musta made it through time as a talking head or something. He said roughly the same thing - "You go to war with the army you have---not the army you might want or wish to have at a later time."

 

[Condottiere]

If the tankers use drop tanks, after emergency refueling before the discrete withdrawal of the expeditionary task force, the tankers then subsequently blow the empty tanks and with the reduced tonnage, make a run for it.

 

[Reynard]

"You always jump blind into a system. Any intel you might get will be two weeks old - one week to jump to the waiting fleet with the info, one week to jump back into the system. Thus your info is always at least two weeks old."

Sorry, what I meant was you have a strategic understanding of the environment you are jumping into. I doubt most group enter a system never surveyed before and, if a system is important enough, scouts would be sent to spy on activity. Populated systems will often be known to have the capability of local defense which can be taken into account with your objective as well as its importance to regular enemy fleet movement.

I remember the game Fifth Frontier War in which you planned your fleet moves, I believe, six weeks in advance so each side were blind to each other's movement and that means you were never sure if enemy fleets might be in a system you enter unless you detected evidence of a pattern or planned for objectives that would involve opposition.

If you enter a system far from a fuel source and into the jaws of naval opposition capable of denying fuel access, it was terrible luck or very terrible planning.

 

[GypsyComet]

There are both simplifications for casual players (ie. those NOT INTERESTED in being amateur accountants just to play an RPG), and metagame decisions (keep the PCs needing fuel, and thus money) at work in Traveller, and specifically in CT, T4, T20, MGT, and T5. If you want precision in fuel handling and powerplant management, go look at MT or TNE (or the mess that is T4's FF&S). A simpler approach that is, sadly, incompatible with Mongoose letter drives is presented in T4's lower levels of ship construction (QSDS and SSDS).

The "problem" is that a working high detail power and fuel model doesn't exist for the CT/MGT/T5 consumption model, though T4 certainly tried. TWICE. The minute someone tries to come up with one, the power assumptions from other editions will leak in to either the writing or the opinions of those who asked for it in the first place.

Since this is the Mongoose board, let's stick to the basic tools we have in that edition. Letter Drives, at least at the small ship and subcraft levels, make it more of a challenge, but if this isn't wholly compatible with ships built out of the core book it is a total non-starter.

Let me start with a reasonable assumption, given that it reflects exactly how MGT small ships are built: the fuel consumption listed is the amount required to run that rating of Power Plant AT FULL OUTPUT. The moment you step to a more detailed model, those durations go out the window.

More later.

 

[Reynard]

Drop tanks don't affect the 100D limit or visa versa. High Guard refers to drop tanks as Jump tanks and are jettisoned at the moment of a jump with possible misjump risk. These tanks carry enough fuel needed for a single jump meaning the ship has full jump fuel at the destination. This is either for a strategic jump without refueling at the first location, having jump fuel in a system without fuel sources or expecting the possibility of an emergency jump if the destination proves deadly. I can see scout craft on recon doing this more often than other ships.

That said, the extra fuel has no effect on jump risk due to the 100D limit. You still use your maneuver fuel to reach the 100D limit though the displacement of the drop tanks and fuel should affect the efficiency of the drive unless it's considered minimal. At the moment of jump, the fuel is used, the tanks are removed and displacement is normalized.

I remember a space combat game that actually had you track fuel depletion and subsequent increased engine efficiency but the extra 'realism' was horrendous for book keeping and didn't make the game any better.

 

[GypsyComet]

A main element is KISS so that those groups who do not care can ignore it (like in MT where ships are rated at 2 weeks+jump) and those who like it can use it easily. Do not go the TNE way (Heplar fuel guzzlers) where "looking at the gauges" was basically unavoidable im gameplay

My goal would be to provide a set of formulas no more complex than MGT High Guard contains (for other things), but which is aimed primarily at CRB users. It *might* be mappable to the percentage drives of MGT HG, but that would be a bonus, not the prime goal. PC ships are my primary concern.

 

[Condottiere]

I wasn't recommending that in this particular case starships should have had drop tanks attached (though I tend to see it as an option) but rather that the tanker would have them, and if the situation was untenable, would drop them after refueling the rest of the task force, and with a much lower tonnage, jump out on the emergency reserve.

 

[Jacqual]

That is why I myself miss CT with the basic 28 day Powerplant fuel supply, it gave ships that safety net of getting to a fuel depot in a system whether it was a gas giant, water world, Iceball, or Galactic Bob's Self Serve Fuel Depot.

btw anyone that wants can use Galactic Bob's Self Serve Fuel Depot, I won't mind

 

[phavoc]

I found the fuel reference in Arrival Vengeance supplement, for those that are interested:

Power plant output indicates cruise output (maneuver, lie support, commo, sensors. )/maximum output (full combat consumption plus redundancy). The duration figure given reflects the fact that the design has been optimized for 30 days (720 hours) of cruising with sufficient additional fuel
for four ditional days (96 hours) of continuous combat. Time spent in combat over the four day figure consumes fuel at a rate 3.72 times that of the missing figure (each hour of combat used fuel equivalent to 3.72 hours of cruising). Maximum additional combat time is eight days (193.5 hours)
without eating into the jump fuel.

 

[GypsyComet]

Arrival Vengeance was very late MT, after the partial fuel use revelation. Those aren't just WAG numbers, they were part of the design process.

 

[Egil Skallagrimsson]

When a free trader enters a system after a jump it might only have 4-6 days of fuel left.

A inaccurate jump into a system with the only gas giant on the other side of the star would leave the ship stranded.

If you calculate the odds, inaccurate jumps are an everyday occurrence.

But how inaccurate is an inaccurate jump? The CRB talks about "somewhere in the outer system", it is really up to the GM how much extra travel time to add.

Anyway, this is the chance for the Engineer to dust off his Power Plant skill, and try to coax that little bit of efficiency out of the fuel.

Egil

 

[Egil Skallagrimsson]

Another vote from me for the "it's a game, keep it simple" school of thought.

The peculiarities of the jump drive and its requirement for lots of fuel to jump, are part of the game design assumptions, and allows a base to construct the parameters of space going upon. Trying to make real world assumptions about a fictional construct is always going to be a bit tricky

If you need a justification for the, apparently, high power consumption in jump, then hand wave away on the idea that the power is needed to maintain the jump bubble.

Of course, the CRB puts forward some good ideas for alternative game FTL, so if you don't like jump drive, pick another game assumption (or carry some more fuel, your choice).

Egil

 

[dragoner]

Another vote from me for the "it's a game, keep it simple" school of thought.

Egil

Pretty much; if someone doesn't like the two weeks worth of fuel, just redline it and make it four.

 

[phavoc]

That's rather silly logic "it's a game, keep it simple". I'm not looking for FF&S level of complexity, but High Guard introduces a great deal of non-simple issues. Adding in supplements like Merchants and Cruisers, Central Supply Catalong, Sector Fleet, et al, all introduce additional complexity. Hell pretty much every supplement outside of the CRB introduces complexity and makes the game "less simple".

Having a good, reasonably rational foundation upon which to layer the game is never a bad idea. Otherwise there would never be the point to create a starship at all - just put together whatever it was you wanted and pronounce it acceptable.

Except that doesn't seem to be the case with Traveller. I wasn't a big fan of some of the changes that came about in MT as far as the design sequences were - it seemed to be getting further from the game play. But I've loved the added "complexity" of additions like GURPS whereby the new information could be used, or not, but at least it was there and it was a reasonable and solid foundation upon which more adventure could be drawn upon. At the least it allowed those who wanted more materials to tailor their adventures to have more depth.

I really don't get the complaints about better explanations for those who like them. Isn't that what the board (and thread) is all about? If you didn't want to do more, think more or ask more, why bother even responding to the threads to call out those who do want more?

 

[dragoner]

Complexity comes at the cost of playability.